Noncorrosive steel alloy



Patented Dec. 27, 1932 UNITED STATES PATENT OFFICE H. ALTON IHTCHELL ALFRED W. GREGG, AND RAYMOND H. FRANK, 0F COLUMBUS,

OHIO, ASSIGNORS TO THE BONNIW-FLOYD COMPANY, OF COLUMBUS, OHIO, A. 603- I PORATION OF OHIO NONCORROSIVE STEEL ALLOY Ho Drawing.

This invention relates to alloys and has for its primary object the provision of an inexpensively produced and mechanically strong composition matter which posseses properties whereby the alloy is capable of withstanding repeated exposures to high temperatures without any substantial oxidation, disintegration or other changes in its physical or chemical form.

It is a particular object of the present invention to provide an inexpensive alloy which will resist oxidation or corrosion to practically the same degree as chromium. containing alloys and at the same time to provide an alloy which is highly resistant to abrasion and capable of resisting change in form or loss of physical strength upon exposure to abnormally high temperatures.

Corrosion resisting metals havin substantially the above named attributes, ave been produced from alloys containing high percentages of chromium and nickel and serve quite efiectually the uses to which they are put, but their expensiveness is in many instances prohibitive for most purposes, and the same is true of many other compos tions or alloys heretofore proposed for such uses.

Another object of the invention is to secure a' corrosion resistant alloy suitable for most practical purposes, and one which does not necessitate the use of expensive ingredients or require unusually expensive processes of manufacturing.

Although special substances may be added for special urposes the improved material com rising t e present invention is ordinarily ma e from an alloy containing essentially the following ingredients, (the first column showing the preferred species and the second column showing the permissible variations).

Per cent Per cent Carbon .50 Trace to 1.50

Manganese 14.00 3.00 to 18.00

uminum 11.00 5.00 to 25.00

Silicon .50 Trace to 1.00

The balance being iron with the exception of such incidental impurities as phosphorus and sul hur.

connection with the above it may be desirable to add to the alloy small quantities is entirely unsuitable for Application filed December 26, 1929 Serial No.416,764.

of nickel, molybdenum or chromium in quan tities varying between 1% to 5% of the total materials present. The addition, however, of any one of the three, either singly or collec tively, arises as the result of special conditions since ordinarily the improved alloy comprising the present invention does not contain these more expensive materials.

The iron constitutes the base of the alloy and gives the desired cheapness. The manganese and aluminum in the proportions specified constitute the outstanding ingredients used in our alloy. Aluminum alone has been suggested heretofore as an ingredient in a ferrous alloy for resisting the detrimental influences of corrosion. However, aluminum alone produces ferrous alloy of rough, friable, grain structure and thus while it produces an alloy which will resist corrosion practicable application. We have found, however, that by employing in conjunction with aluminum the specified quantities of manganese the grain structure is improved and a metal produced which is both corrosion resisting and-adaptable to practical usages. When the carbon content is low the alloy may be readily subjected to the manufacturing processes of articles made from steel, however, the alloy is an improvement over steel and other analogous alloys by reason of its greater resistance to oxidation, its abrasive resisting qualities and its capability of withstanding high temperatures without loss of its desirable properties. The product may be made by the employment of ordinary manufacturing processes common in the production of ferrous alloys. Preferably, the ingredients are reduced to a molten state in an electrically heated furpace but the temperatures necessary in attaining this molten state may be obtained from any other of several well known types of metal heating furnaces now in general use. It will be observed that the ingredients comprising our alloy are cheaply and easily obtained and since the manufacturing process is substantially the same as that in producing other ferrous alloys, the present product is of low cost as compared with alloys containing high percentages of chromium, nickel and similar high cost ingredients.

Having thus described the invention what is claimed is: v

1. A non-oxidizing alloy containing the following ingredients in substantially the relative proportions given:

Per cent Carbon; Manganese 14.00 Aluminum 11.00 Silicon .50

the balance being principally iron with the exception of incldental impurities such as phosphorus and sulphur.

2. A non-oxidizing alloy containing the following ingredients in substantially the relative proportions given:

Per cent Carbon Manganese 14.00 Aluminum 11.00 Silicon .50

Chromium 1.00 to 5.00

I the balance being iron with the exception of incidental impurities such as phosphorus and sulphur.

3. A non-oxidizing alloy containing the following ingredients in substantially the relative proportions given:

Per cent Carbon Manganese 14.00 Aluminum 11.00

( Silicon .50

Nickel 1.00 to 5.00

the balance being iron with the exception of incidental impurities such as phosphorus and sulphur.

4. A non-oxidizing alloy containing the following ingredients in substantially the relative proportions given:

Percent Carbon .50 Manganese 14.00 Aluminum 11.00 Silicon .50 -Molybdenum 1:00 to 5.00

the balance being iron with the exception of incidental impurities such as phosphorus and sulphur.

In testimony tures.

whereof we aflix our signa- H. ALTON MITCHELL. ALFRED W. GREGG. RAY. H. FRANK. 

